Table 3.
Univariate analysis of variables of overall survival and disease-specific survival in the Surveillance, Epidemiology, and End Results (SEER) Database
| Characteristic | Overall survival | P value | Disease-specific survival | P value |
|---|---|---|---|---|
| Race | .665 | .514 | ||
| Caucasian | 1.000 (reference) | 1.000 (reference) | ||
| Non-Caucasian | 1.147 (0.618-2.129) | 1.231 (0.660-2.298) | ||
| Sex | .445 | .615 | ||
| Female | 1.000 (reference) | 1.000 (reference) | ||
| Male | 1.197 (0.755-1.898) | 1.131 (0.700-1.828) | ||
| Age at diagnosis (y) | 1.020 (1.006-1.034) | .004 | 1.018 (1.004-1.032) | .013 |
| Primary site | .048 | .033 | ||
| Single lobe | 1.000 (reference) | 1.000 (reference) | ||
| Involving more than 1 lobe | 2.875 (1.011-8.176) | 3.154 (1.098-9.058) | ||
| Tumor grade | .625 | .751 | ||
| Low grade (Ⅰ-Ⅱ) | 1.000 (reference) | 1.000 (reference) | ||
| Advanced grade (Ⅲ-Ⅳ) | 1.301 (0.453-3.731) | 1.189 (0.409-3.448) | ||
| Laterality | .138 | .137 | ||
| Right | 1.000 (reference) | 1.000 (reference) | ||
| Left | 0.702 (0.440-1.121) | 0.691 (0.425-1.124) | ||
| Histologic subtype | .245 | .296 | ||
| Spindle cell | 1.000 (reference) | 1.000 (reference) | ||
| Epithelioid cell | 4.600 (0.586-36.090) | .147 | 4.341 (0.553-34.104) | .163 |
| Biphasic | 0.693 (0.266-1.806) | .453 | 0.745 (0.284-1.953) | .549 |
| Surgery performed | <.001 | <.001 | ||
| No | 1.000 (reference) | 1.000 (reference) | ||
| Yes | 0.261 (0.156-0.438) | 0.243 (0.138-0.399) | ||
| Radiation therapy | .004 | .003 | ||
| Yes | 1.000 (reference) | 1.000 (reference) | ||
| No | 2.250 (1.303-3.885) | 2.392 (1.344-4.260) | ||
| Treatment modality | .007 | .003 | ||
| Surgery with radiotherapy | 1.000 (reference) | 1.000 (reference) | ||
| Surgery only | 0.500 (0.273-0.914) | .024 | 0.462 (0.246-0.869) | .017 |
| Radiotherapy only | 1.992 (0.708-5.602) | .191 | 2.272 (0.791-6.522) | .127 |
| LN involvement | <.001 | <.001 | ||
| No | 1.000 (reference) | 1.000 (reference) | ||
| Yes | 3.436 (1.782-6.625) | 3.684 (1.896-7.158) | ||
| Distant metastasis | <.001 | <.001 | ||
| No | 1.000 (reference) | 1.000 (reference) | ||
| Yes | 2.559 (1.538-4.259) | 2.724 (1.613-4.598) | ||
| Tumor size, cm | .001 | .001 | ||
| ≤5 | 1.000 (reference) | 1.000 (reference) | ||
| >5 | 3.540 (1.665-7.525) | 3.887 (1.741-8.677) | ||
| AJCC stage | <.001 | <.001 | ||
| Ⅰ-Ⅱ | 1.000 (reference) | 1.000 (reference) | ||
| Ⅲ-Ⅳ | 3.098 (1.760-5.453) | 3.241 (1.817-5.780) |
Values are presented as hazard ratio (95% CI). LN, Lymph node; AJCC, American Joint Committee on Cancer; Met, metastasis.